Electronic typewriter

ABSTRACT

In an electronic typewriter, the ends of fifteen needles are arranged in three parallel rows of five needle ends each which, for each typing operation, are selectively withdrawn under the control of a diode matrix or of input data so that the remaining ends form a selected alpha-numeric character. An ink ribbon superposed on a paper in turn superposed on the needle ends is brought against the paper by a tracer anvil to effect printing. Carriage return and other such operations are provided for, as well as illumination of the printing zone and a line shadow for alignment of the paper.

United States Patent [191 Oliveira ELECTRONIC TYPEWRITER [75] Inventor: Alvaro Manoel Noya Dias Oliveira,

Porto, Portugal [73] Assignee: Sociedade de Representacoes Santos Guimaraes & Oliveira, S.A.R.L., Porto, Portugal [22] Filed: May 13, 1971 [21] App1.N0.: 143,042 9 [30] Foreign Application Priority Data May 14, 1970 Portugal 53801 [52] U.S. Cl. 197/1 R, 197/190 [51] int. Cl B4lj 3/50 [58] Field of Search 197/1, 2; 33/62 Primary ExaminerRobert E. Pulfrey Assistant ExaminerR. T. Rader Attorney, Agent, or FirmWaters, Roditi, Schwartz & Nissen [57] ABSTRACT In an electronic typewriter, the ends of fifteen needles are arranged in three parallel rows of five needle ends each which, for each typing operation, are selectively withdrawn under the control of a diode matrix or of input data so that the remaining ends form a selected alpha-numeric character. An ink ribbon superposed on a paper in turn superposed on the needle ends is brought against the paper by a tracer anvil to effect printing. Carriage return and other such operations are provided for, as well as illumination of the printing zone and a line shadow for alignment of the paper.

5 Claims, 9 Drawing Figures PATENTEDAPR-SO 1914 SL807 5455 sum 2 0 7 PATENIEB R j3.807;545

- SHEEIU-UF? Amp/Mews 3 PATENTEDAPR'SG 1814 3807545 sum 5 OF 7v 24V v I PATENTEBAPR 30 I974 SHEET 6 [1F 7 ELECTRONIC TYPEWRITER FIELD OF THE INVENTION This invention relates to electronic typewriters.

BACKGROUND There are at present on the market three kinds of typewriters, the classifications of which, according to their principle of operation are mechanical, electrical and electronic. In the electrical and electronic categories, various mechanical arrangements are also employed.

The high writing speed and efficiency of electronic typewriters have resulted in their extensive use in large business enterprises. However, in small and medium business enterprises, the greatest hindrance to the wide spread use of electronic typewriters is their high cost. This problem is still more keenly felt when it is necessary that these typewriters include data input and output circuits.

SUMMARY OF INVENTION It is an object of the present invention to provide an improved electronic typewriter which, for example, has only fifteen'(plus three auxiliary) data input and output lines so that it can operate as a peripheralunit for printing alpha-numeric characters, which features an extreme minimization of production cost and very simple maintenance, and which is characterized by a new and improved way of placing and illuminating paper of any type and quality.

These above objects are attained, essentially, by the following features:

a. The use of a minimal number of dots for the formation of, for example, forty-three alpha-numeric symbols employed in the illustrated machine; since there are only fifteen dots available for the formation of the symbols, the input and output of data relating to the symbols can take place through fifteen lines only;

b. From the use of a minimal number of dots derives the simplification of the novel machine since basically it consists of a chassis with a body, carriage, electric motor, keyboard, matrix of diodes, transistors and electromagnets; this simplification results in a reduced cost of production and also in great ease of service and maintenance;

0. The paper is so placed and struck in dot-style to form the various symbols as follows:

The paper is fixed between the platen of a carriage and pressure cylinders; the attack is on the back of the sheet of the paper in a process hereinafter called the backprinting" process; a tracer, which includes a conventional inked ribbon driven by an electromagnet, presses the paper onto backprinting needles to form dots as subsequently described in detail;

Illumination of the writing zone is obtained with tubular lamps having horizontal filaments; between these lamps and the paper is interposed a nylon thread whose shadow, of sharp contour due to the type of lamp, defines a guide line for the alignment of the writing; another lamp, which is part of an optical system, projects through the orifice ofa plate, a light beam focused on the area where the symbol is to be printed.

BRIEF DESCRIPTION OF DRAWING FIG. I is a chart illustrating different needle end arrangements for different alpha-numeric characters in accordance with the invention;

FIG. 2 is a diagrammatic perspective of the printing portion of a typewriter employing needles in accordance with theinvention;

FIG. 3 is a block diagram illustrating controls for the typewriter of FIG. 2 as well as operational phases relating to the same;

FIG. 4 is a schematic diagram of a diode matrix employed in the control of FIG. 3; I

FIGS. 5-7 are schematic diagrams. of circuit details of the block diagram of FIG. 3;

FIG. 8 is a schematic diagram of further circuit details relating to FIG. 3; and

FIG. 9 is a perspective view of the mechanical configuration of a part of the apparatus of FIG. 2.

DETAILED DESCRIPTION The illustrated embodiment of the invention uses fifteen'needle ends or dots for the formation of 43 alphanumeric symbols as shown in FIG. 1. Since only fifteen dots are used for the formation of thesymbols, the input and output of data relating to the symbols can take place through only fifteen lines.

The needle ends are juxtaposed in three parallel lines of five ends each, all of the ends having a position of rest in a plane from which the ends are selectively withdrawn so that the ends remaining in said plane constitute the selected symbol.

The diagrammatic perspective view of FIG. 2 shows how the needle ends are selected. Therein the paper 1' is fixed between the platen of a carriage 2' and pressure cylinder 3. As the attack is made on the back 9' of the sheet I of paper, face 8' being the surface turned toward the operator, the process is called a backprinting" process. A tracer or anvil 4, which operates on a conventional inked ribbon 10 driven by an electromagnet 5', presses the paper 1 onto the backprinting needles 6' to form the dots which constitute the alphanumeric symbols.

Illumination of the writing zone is obtained with tubular lamps having horizontal filaments 15. Between these and the paper is interposed a nylon thread 16 whose shadow l7 of sharp contour due to the type of lamp, defines a guide line for the alignment of the writing. Another lamp 18, which is part of an optical system, projects, through the orifice of a plate l9,'a light beam focused on the area 20 where the symbol is to be printed.

A machine of the invention is shown in block diagram form in FIG. 3. It includes a keyboard (such as the AZERT) having forty-three keys corresponding to a like number of alpha-numeric symbols. Each key, when depressed, establishes a contact closing an electronic circuit.

Also included is a diode matrix 2 which has 45 inputs, 43 of which correspond to the alpha-numeric symbols used, the others corresponding to the space bar and the carriage return key. In the present embodiment, the matrix 2 has eighteen outputs which connect with as many power amplifiers. By inspection of the diode matrix of FIG. 4 (which shows the details of matrix 2), it can be seen how data are obtained which constitute the information transmitted to the following stage (power ampfliers 3) or to the input stage of any other peripheral component of a data processor.

For easier comprehension of FIG. 4, there are indicated below, for each input (seethe chart of FIG. 1) of the matrix of diode 30, the outputs shown in the following table:

INPUT OUTPUTS A 1' 7 8 10 ll 16 B 7 '9 ll 13 l5 16 C 1 5 7 8 9 12 I3 14 16 C l 4 7 8 1O 12 13 14 16 D 7 8 9 ll 15 E 7 9 l2 l4 16 F 7 9 1O 12 14 15 16 G 1 5 7 8 I 9 12 16 H 6 7 9 1O 16 I l 2 3 '4 5 11 1213 1415 16 .I 2 3 4 7 8 9 IS 16 K 6 8 l l2 l3 l4 16 L 6 v 7 8 9 1] I2 13 1416 M 6 8 9 l0 16 N 7 8 9 1O 11 16 O l 7 8 9 ll l5 16 P 7 9 It) ll l3 l4 l5 16 Q l 4 5 7 8 I0 ll l4 16 R 7 9 IO ll l3 16 S l 3 4 7 9 12 13 l5 16 T 2 3 4 5 l2 13 I4 15 16 U 6 7 8 9 16 V 5 6'. 7 8 9 l5 15 w 6 7 s 10 16 X 3 6 7 9 l0 l3 16 Y 3 4 5 6 7 l3 l4 16 Z 2 3 7 9 13 14 I6 I l 3 5 6 8 10 ll l3 15 16 l 2 4 5 6 10 ll 12 1415 16 1 l 2 3- 4 5 6 8 I0 1112 13 1415 l 2 4 5 6 7. 9 10 ,1112. 14 r l5 l6 l 2 3 4 5 6 7 8 911 12 1315 1 6 I 2 3 4 5 6 8 9 1112 13 Y 1415 n l l 3 4 II 12 13 l4 l6 2 2 3 7 9 ll l3 l4 l6 3 2 4 7 9 ll 13 15 16 -4 4 5 6 7 9 IO 16 5 4 7 9 l2 l3 15 16 6 l 7 9 I2 l3 l5 l6 7 2 3 7 9 i .l0 l3 l4 l5 l6 8 l 3 5 7 9 ll 13 15 16 9 1 3 4 7 9 l5 l6 0 l 5 7 8 9 ll I5 16 Space 17 Carriage return 18 In the illustrated embodiment, there are fifteen power amplifiers 3 which feed the coils of the backprintingelectromagnets and whose imputs are connected to fifteen of the outputs of the matrix of diodes. The three remaining:

Output 16 (common to all inputs in FIG. 4) is coupled to two power amplifiers, TFE l6 and TC 16 (FIG. 8), which it is necessary to actuate with all alphanumeric symbols. TFE 16 serves to trip the relay R which closes the feed circuit of the coils of two electromagnets E1 and E2 (E1 actuates the carriage release and the spacing; E2 controls the transport of the inked ribbon). Lastly, TC 16, which provides greater power, feeds coil 7 (FIG. 2) of the electromagnet 5', which controls the descent of the tracer 4'.

Output 17 is coupled directly to the input of the amplifier TFE 16, with interposition of a diode D (FIG. 8) intended to block the descent of the tracer when the space key is depressed.

Output 18 is coupled (FIG. 8) to a power amplifier The circuit used for all of the amplifiers is the same (FIG. 5) except that, in the amplifier TC 16 which supplies greater power (FIG. 6), the type of transistor is different as are consequently, the coil B of the electromagnet and the values of'the resistances R and R of polarization. A potentiometer P is provided which is accessible to'the operator who, by regulating the base current of the. transistor TC 16, controls the'pressure which the tracer exerts when it comes down on the paper.

The coils B (FIG. 5) of electromagnets 4 (FIG. 3) are in series with the collectors of the transistors T of the power amplifiers. When the transistors are in a state of conduction (to which state they pass when the base becomes negative), the current flowing in the coils energizes them, the electromagnets are operated and attract the armatures 13, at the end of which and rigidly connected thereto are the backprinting needles 6 (FIG. 2).

The formation of the alpha-numeric symbols is indicated at block 5 in FIG. 3. Therein, the needles 6' are slightly withdrawn (as is seen at A, FIG. 2), when the armatures 13 of the backprinting electromagnets 11' are attracted by the cores 12.

Relative to the electromagnets which are not operated, the needles remain in their initial positions (as is seen at B, FIG. 2). This latter position of the needles is coincident with the plane defined by the back 9' of the paper 1' to be printed upon (FIG. 2). I

Actuation of the tracer 4 and entrainment of the inked ribbon 10 is indicated by block 6 in FIG. 3. The tracer 4, which operates on conventional inked ribbon 10, is actuated by the electromagnet 7 of greater power, and descends onto the paper and, by pressing it against the needle ends, carries out the printing of the selected symbol. After the tracer has come down, the ribbon is moved along to a new position (FIG. 2). The operations of phases 5 and 6 constitute the printing of the alpha-numeric symbols.

The carriage return indicated in phase 7 is carried out when, after the corresponding key has been pressed by the operator, a contact is established which operates an electromagnet, which transmits the movement of an electric motor to a suitable mechanical system which, in turn, brings the carriage back to a fixed position for the start of a new line. The carriage return can also be carried out automatically if, when the carriage reaches a predetermined position, an electric contact is established which causes the same operation as described above.

The rotation of the platen, which is also indicated in phase 7, is necessary when the start of a new line is reached. This is obtained with a suitable mechanism, which is actuated in accordance with the position'selected on a conventional line space lever, by the carriage itself when it'returns.

The carriage release of phase 8 is obtained from output 16 of the matrix 2 (FIG. 4) which, as has been noted, is common to all keys corresponding to the alpha-numeric symbols.

Spacing is achieved by means of a space bar which, like any other key, is connected to one of the inputs of the matrix 2, the respective output 17 (FIG. 8) being coupled to an amplifier TFE 16 (FIG. 8) which energizes, through the contact established by the relay R (FIG. 8), an electromagnet El (FIG. 8). So that the tracer will not descend when it is desired to obtain a printfree space, there is provided diode D (FIG. 8) which prevents the passage of the signal coming from the space bar, to the base of TC 16 which, in this way, is blocked. As the space bar is pressed, the carriage then advances by as many spaces as contacts have been established by the operator. I

The operations described in combined phases 7 and 8 constitute the additional movements of the carriage for writing.

As has been noted, the machine has a matrix of diodes with forty-five inputs, forty-three of which correspond to the alpha-numeric symbols selected and the remaining two corresponding to the space bar and the carriage return key, and eighteen outputs, of which fifteen transmit the data relating to the symbols and three transmit synchronization signals for perfecting the contents of the information.

At this time it is of interest to refer only to the part concerning the data. When the machine operates under the control of an operator and independent of outside control (i.e., simply as an electronic typewriter), the eighteen outputs of the matrix of diodes are coupled to corresponding power amplifiers which energize electromagnets, fifteen of which relate to the backprinting needles.

Whenever the machine operates in association with any other peripheral machine of a data processor, and with the same language, it must then send and receive information. The input data will be applied to the power amplifiers and the data output will be removed from the diode matrix 2. Whether for input or for output of information referring to the formation of symbols, there are fifteen reversible lines of access. The data input-output is indicated at block 9.

Besides these fifteen lines, the machine has three reversible lines I6, 17 and 18 (FIG. 8) for input and output synchronization signals, two of them relating to the synchronization of carriage release, spacing, inked ribbon entrainment and actuation of thetracer, and the third line relating to the synchronization of carriage return and platen rotation.

In fact, when the machine is linked with another peripheral data processing machine, using the same language, there must be synchronization between them, sent by the machine emitting the information which, having arrived at the information receiving machine, controls the latter with respect to: feed of the inked ribbon, actuation of the tracer, carriage release, spacing, carriage return, and platen rotation.

In the machine being described, each two of these operations occupy one synchronization line. Thus, one line transmits the signal for inked ribbon drive and actuation of the tracer simultaneously (line 16, FIG. 8); another line transmits the signals for carriage release and spacing not simultaneously, but one not excluding the other (line 17, FIG. 8), and through the third line flows the signal for carriage return which, as has been noted, automatically involves the rotation of the platen. These three lines are reversible and serve either for input or for output of the synchronization signals. This is indicated at block 10.

For the electronic operation of this machine, there have been fixed two direct current feed voltages 24V and +3 V. These are supplied by current sources 11.

The first is available at the output of a full-wave rectifier 40 (FIG. 7) which is coupled to the secondary 42 of a transformer 44 whose primary 46 is fed by a line voltage, for example 220V at 50 or 60 Hz.

The second (+3V) isavailable from two mercury cells of 1.5V each, connected in series and easily removable, as indicated at 48 in FIG. 8.

A writing operation is commenced by the insertion of paper into the machine. The paper is fixed in desired place with the aid of an easily manageable lever (not shown) which controls the pressure cylinder 3' (FIG.

To insure correct alignment of the writing of the symbols, there is formed on the paper a guide line which is obtained by the projection of the shadow 17' of a nylon thread 16 situated between the paper and a luminous source formed by tubular lamps 15' having horizontal 20 corresponding to the assembly of the fifteen needles indicating the exact point where the symbol is to be printed. It is thus possible, during a writing period, to remove the paper and to re-insert it, matching with precision that which is yet to be written with what has already been printed on the paper (e.g., when a word is to be completed).

Since the formation of the forty-three alpha-numeric symbols is the same for all, there will next be described only how one of them is obtained, for example, the letter H.

In FIG. 1, image IX, corresponding to the symbol H, indicates that of the fifteen backprinting electromagnets only those corresponding to the needles 6, 7, 9 and 10 will be operated. This takes place as follows:

On depressing the key corresponding to the letter H, a negative voltage is applied to the cathodes of the diodes DH6, DH7, DH9 and DHlO (FIG. 4) connected to the input 2 (FIG. 8) designated by H in the diode I matrix (FIG. 4).

As a result of the arrangement given to the diodes in the matrix, due to the fact that the diodes referred to (DH6, DH7, DH9, and DH10) are directly polarized, the power amplifier transistors T6, T7, T9, and T10 (FIG. 8) become conductive so that there flows in the coils of the corresponding backprinting electromagnets B6, B7, B9 and B10 a current which energizes them,

causing the attraction of the armatures' 13' (FIG. 9). These, in turn, rock at pivot 14 (FIG. 9) and cause the withdrawal of the needles 6, 7, 9 and 10 rigidly connected to the free ends of the armatures.

The needles 6, 7, 9 and 10 being withdrawn, the others, which remain at rest, are the ones that define the selected symbol, in this case the letter H. As these neeneedles occurs before the arrival of the tracer on the 1 face of the paper because the stroke of descent of the tracer is greater than the stroke of withdrawal of the needles and because the tracer stroker takes a finite time at the beginning of which the needles are already withdrawn.

After the descent of the tracer, when the latter starts to go up, the inked ribbon advances to a new position,

as doesthe carriage (release movement), the system being thusready for the printing of the next alphanumeric symbol.

In the foregoing, reference has been made to AZ- ERT. As is known difi'erent keyboard arrangements are in use throughout the world and this term is used simply as an indentification of one particular arrangement where the upper line of letters begins, from the left, with these letters in the order given.

Further, in FIGS. and 6, transistors are employed and can readily be selected. By way of example however, there can be employed, in FIG. 5, ASY 80 or any equivalent transistor and, in FIG. 6, A82 or any equivalent transistor.

As to the needles shown in FIG. 2, there were employed needles with the following specification:

Material inox steel Diameter 0.6 mm.

Length I35 mm These are exemplary only as various other sizes and materials can be used.

What is claimed is:

l. A typewriter apparatus for printing on a paper comprising a plurality of needles including ends arranged, prior to printing, in a group in a fixed position in a printing zone below said paper, means for withplurality of alpha-numeric symbols, means for supporting paper in a horizontal plane" adjacent said zone, means for forcing the paper against the ends remaining in said zone and for effecting an inking-operation in correspondence with the latter said ends for printing of said selected symbols, a keyboard for selecting said symbols and a matrix responsive to the keyboard to select said needles, the said means for forcing including a reciprocable anvil, an ink ribbon between the anvil and paper and engageable by said anvil to be forced against the paper at said zone, means to transport the ribbon past the anvil between printing operations, means to project a shadow of a line across the width of the paper to permit alignment of an entire line of printing, and means for illuminating an individual character along said line of printing.

2. Apparatus as claimed in claim 1 wherein the said means for withdrawing includes electromechanical devices coupled to and operated by said matrix and links between said electromechanical devices and needles.

3. Apparatus as claimed in claim 1 wherein the needles and said means for forcing are on opposite sides of the paper.

4. Apparatus as claimed in claim 1 wherein the needles ends have a position of rest in a plane in said zone.

5. Apparatus as claimed in claim 4 wherein the needle ends are arranged in parallel rows forming a rectangle. 

1. A typewriter apparatus for printing on a paper comprising a plurality of needles including ends arranged, prior to printing, in a group in a fixed position in a printing zone below said paper, means for withdrawing, in each of a sequence of printing steps, selected of said needles so that the ends remaining in said zone in each of said steps corresponds to selected of a plurality of alpha-numeric symbols, means for supporting paper in a horizontal plane adjacent said zone, means for forcing the paper against the ends remaining in said zone and for effecting an inking-operation in correspondence with the latter said ends for printing of said selected symbols, a keyboard for selecting said symbols and a matrix responsive to the keyboard to select said needles, the said means for forcing including a reciprocable anvil, an ink ribbon between the anvil and paper and engageable by said anvil to be forced against the paper at said zone, means to transport the ribbon past the anvil between printing operations, means to project a shadow of a line across the width of the paper to permit alignment of an entire line of printing, and means for illuminating an individual character along said line of printing.
 2. Apparatus as claimed in claim 1 wherein the said means for withdrawing includes electromechanical devices coupled to and operated by said matrix and links between said electromechanical devices and needles.
 3. Apparatus as claimed in claim 1 wherein the needles and said means for forcing are on opposite sides of the paper.
 4. Apparatus as claimed in claim 1 wherein the needles ends have a position of rest in a plane in said zone.
 5. Apparatus as claimed in claim 4 wherein the needle ends are arranged in parallel rows forming a rectangle. 